Much investment has gone toward improving the immersive experience in human-computer interaction. Many industries, such as medicine, architecture, aeronautics, teaching, and manufacturing, have benefited from immersive interactive technologies. Game immersive interaction is a widely publicized market because of its size and of the relative value of improving the users' experience during game-play. This improved experience relates directly to how realistic, how lifelike the game feels to a player. One of the keys to providing this lifelike sense of reality within a game is to register a user's physical world within the digital world created by the computer game system.
Today, the principal technologies involved in registering a user's physical world with a game's computer world have been infrared (IR), inertial, and camera gesture tracking. Each technology adds a different level of interaction and experience for games. Inertial and camera gesture tracking allow a game to sense a user's motion and IR tracking provides some two dimensional pointing functionality for fine-tuning an inertial tracking system. However, each of these technologies has limitations. All camera and IR systems are limited to line-of-sight with the user or user's game controller, and working volumes are restricted by angle of view restrictions and poor depth sensing. Inertial technologies, like those used by gyroscopes, accelerometers, and magnetometers, track motion, not position. For the most part, these technologies focus on improving the gaming consoles made specifically for games that have very large processing power and speed requirements.
A new phenomenon, mobile gaming, has arisen from the enormous success of smart phones and tablets. Users can now download and play games directly on a smart phone or tablet's touch-screen without cost or for a small investment compared to the relatively high cost of console game software. The advance of technology has led to smart phones (a mobile phone built on a mobile operating system, having computing and networking capability) and tablets (mobile computer) with increasingly powerful processing that enable them to operate games directly, without requiring an external game console. In addition, requirements for software developers to produce games for mobile devices have become less restrictive than producing such games for game consoles. These market forces have allowed mobile gaming to become as large as the console gaming market and mobile gaming is likely to surpass console gaming in the near future.
Despite the growing success of mobile games, these games suffer from limited user interface options imposed by a simple and small two-dimensional touch screen. Many mobile games are played by touching a display screen and by using the point of touch as the input point for navigating and controlling the game. Playing games on a small touch screen, with the touch screen as the only input option, produces a limited immersive experience compared to playing on a large television screen. These interface and hardware realities inherently limit a mobile device's level of immersive interaction.